Spark plugs



Sept. 16, 1958 L. P. GENDRON SPARK PLUGS Filed Jan. 10, 1957 United States Patent O 1 2,852,713 SPARK PLUGS Louis Philippe Gendron, St.-Leon-le-Grand, Quebec Canada Application January 10, 1957, Serial No. 633,482 1 Claim. (Cl. 313-123) The present nvention relates to new and useful improvements in ignition devices and more particularly to spark plugs for use with internal combustion engines.

An object of the nvention is to reduce the fuel consumption in the operation of an internal combustion engine by providing a spark plug having electrodes exposed to the fuel mixture in such a manner as to provide instantaneous ignition of the fuel mixture.

Another object of the nvention is to provide a spark plug from which may be derived a plurality of Sparks which enable all of the gas sucked into the cylinders of an internal combustion engine to be utilized, thus developing maximum power.

Still other objects of the nvention are to provide a spark plug that requires no greater electrical current than other ignition devices, easy engine starting and the elimination of fiooding an engine in cold weather.

All of the foregoing and still further objects and advantages of the nvention will become apparent from a study of the following specification taken in connection with the drawings wherein:

Figure 1 is a bottom plan view of my nvention;

Figure 2 is a Vertical sectional view taken substantially on the line 2-2 of Figure 1;

Figure 3 is a fragmentary Vertical sectional view taken at right angle of Figure 1;

Figure 5 is a fragmentary perspective view of the bottom end portion of the spark plug core;

Figure 5 is a fragmentary persepective View of the bottom end portion of the nvention;

Fimire 6 is a transverse sectional view taken substantially on the line 6-6 of Figure 2; and

Figure 7 is a fragmentary Vertical sectional view of the bottom end portion of a modified form of the nvention.

Referring now, to the drawings in detail, it will be seen that the reference character 1 designates a core constructed of porcelain or other suitable material shaped to provide an intermediate body portion 25 having a fiared dependng portion 26 terminating in a pair of legs 27 and 28, spaced at 15, and at its top end portion with a post 29 provided with a metallic electrode 2 threaded therein at 16.

The electrode 2 has formed in its bottom end portion an axial bore or socket 3.

The body 25 of the core 1 and legs 27 and 28 thereof have formed therein downwardly diverging bores for the reception of metallic rods 4 and 6 which extend below the bottom ends of the legs 27 and 28. Rod 4 is extended below leg 28 and enlarged at 11.

Extending laterally from an integral with the metal rod 6 are a substantially straight arm 7 and a curved arm 8. The curved arm 8 terminates belowtand spaced from the bottom end of the metal rod 4 to provide a spark gap.

The porcelain core 1 is supported spacedly at 21 in a metallic body 10 with the body 25 of the core 1 sealed by means of gaskets or the like 12. At the bottom end of the metal body 10 there is formed integral therewith a substantially L-shaped extension 9 terminating below the end portion of the straight arm 7 to provide a second spark gap. Said body is threaded at 13 for screwing to motor block over a gasket 19 and thinned at 14 over extension 9. Body 10 is provided with hexagonal faces 17 and a milled rib 18 bent over gasket 12.

It is particularly to be noted that the terminal 8 is in the form of a flat and relatively thin plate extending 2,852,713 Eatented Sept. 16, 1958 ICC arcuately about the axis and that the horizontal arm of the element 9 terminates at such point as to have the arms of the plate 8 formed with the ends equally spaced from the terminus of 9, the latter being in the same plane as the member 8.

It is also to 'be noted that the threaded portion or skirt 13 of the body 10 is fiared to provide a frusto-conical Chamber for the lower end of the core is compressed laterally as in Fig. 3 to hold the lower endof the element 6 spaced Well away from the wall of the skirt, bottom face of the core being spaced slightly above the bottom face of the skirt 13. This construction provides an arrangement meeting the first object of this nvention.

This construction while highly eicient has the possibility of fouling in case a poor grade of fuel is used. In order to provide a second spark somewhat sheltered from fouling the element 7 is located in the plane of the bottom of the skirt and is supported from upward deflection by the bottom of the core. By this arrangement fouling of the second spark gap is practically impossible.

In the modified form of the nvention, shown in Figure 7, the body 20 of the porcelain core 31 has an elongated extension 32 of uniform diameter which extension 32 has dependng therefrom a pair of legs 33 and 34.

It will be obvious from the aforegoing that when the spark plug is in use the body 10 is mounted in an engine in the usual manner and connected to an ignition system of conventional type by means of the electrode 2. A double spark is created when current is conducted to the bottom end of rod 4 where it jumps to arm 8 and is conducted thereby to arm 7 from which it jumps to the L-shaped extension 9 creating a second spark for'improved ignition in the engine.

Although I have shown and described herein a pre- I ferred embodiment of my nvention it is to be definitely understood that I do not desire to limit the structure of the nvention to this showing, and that any change or changes may be made in said structure and in the arrangement of the several parts within the spirit of the nvention as claimed.

What I claim is:

In a spark plug of the character described, a conductive body having an axial opening therethrough and having a skirt at its lower end downwardly flaring to provide a frusto-conical chamber, a non-conductive core fitted in said body and provided at its lower end with a laterally compressed portion extending into said Chamber to form a pair of spaced legs, the bottom of the core being spaced slightly above the bottom plane of the body, an electrode extending through the core and projecting downwardly from one of the legs to extend below the bottom plane of the body, a second electrode fixed in said body and extending downwardly below the remaining leg, said second electrode having at its lower end a flat terminal extending arcuately about the axis of the core and located in a plane lower that the lower end of the first terminal, a third electrode of L-shape extending downwardly and inwardly from the skirt and having its inner extremity to lie at equal distances from the ends of the arcuate plate, and an arm extending from the second electrode in the plane of the bottom of the skirt and bearing against the lower face of the core.

References Cited in the file of this patent UNITED STATES PATENTS 1,55l,172 Ritchey Aug. 25, 1925 1,660,635 Thompson Feb. 28, 1928 l,805,752 Birdsall May 19, 1931 l,927,621 Wahl Sept. 19, 1933 2,226,71l Dukelow Dec. 31, 1940 FOREIGN PATENTS 820,981 France Nov. 24, 1937 

